Re: [RFC PATCH] spi: Ensure that CS line is in non-active state after setup
On Mon, Mar 9, 2015 at 9:11 AM, Ivan T. Ivanov iiva...@mm-sol.com wrote: On Sun, 2015-03-08 at 20:01 +, Mark Brown wrote: On Fri, Mar 06, 2015 at 05:45:15PM +0200, Ivan T. Ivanov wrote: if (spi-master-setup) status = spi-master-setup(spi); + else + spi_set_cs(spi, false); Why would this be conditional on there not being a setup operation? It's a good idea, I just don't see why the backstop isn't always useful. I was thinking that this is expected to be handled inside setup operation, nothing more. Agree with Mark. It's perhaps a good idea to call unconditionally before -setup(). -- With Best Regards, Andy Shevchenko -- To unsubscribe from this list: send the line unsubscribe linux-arm-msm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC PATCH] spi: Ensure that CS line is in non-active state after setup
On Sun, 2015-03-08 at 20:01 +, Mark Brown wrote: On Fri, Mar 06, 2015 at 05:45:15PM +0200, Ivan T. Ivanov wrote: if (spi-master-setup) status = spi-master-setup(spi); + else + spi_set_cs(spi, false); Why would this be conditional on there not being a setup operation? It's a good idea, I just don't see why the backstop isn't always useful. I was thinking that this is expected to be handled inside setup operation, nothing more. Ivan -- To unsubscribe from this list: send the line unsubscribe linux-arm-msm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [RFC PATCH] spi: Ensure that CS line is in non-active state after setup
On Fri, Mar 06, 2015 at 05:45:15PM +0200, Ivan T. Ivanov wrote: if (spi-master-setup) status = spi-master-setup(spi); + else + spi_set_cs(spi, false); Why would this be conditional on there not being a setup operation? It's a good idea, I just don't see why the backstop isn't always useful. signature.asc Description: Digital signature
[RFC PATCH] spi: Ensure that CS line is in non-active state after setup
When drivers didn't provide setup() method, SPI core should ensure that CS line is driven in non-active state after spi_setup(). Signed-off-by: Ivan T. Ivanov iiva...@mm-sol.com --- drivers/spi/spi.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index c64a3e5..bfba2d9 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -1895,6 +1895,8 @@ int spi_setup(struct spi_device *spi) if (spi-master-setup) status = spi-master-setup(spi); + else + spi_set_cs(spi, false); dev_dbg(spi-dev, setup mode %d, %s%s%s%s%u bits/w, %u Hz max -- %d\n, (int) (spi-mode (SPI_CPOL | SPI_CPHA)), -- 1.9.1 -- To unsubscribe from this list: send the line unsubscribe linux-arm-msm in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
